The manufacture of many products, particularly medical products requires careful quality control to ensure compliance with product specifications. It is common practice to mark the dispenser and any packaging therefor with various codings and serial numbers for use in checking final product integrity. Widely used marking techniques include printing and the use of bar codes.
There are two well-established methods of monitoring quality in a manufacturing method. The first which is often known as ‘Quality Control’ or ‘QC’ involves checking of the quality of a finished product against a defined set of compliance criteria and rejecting any finished products which do not meet all of the criteria. The second method, often referred to a ‘Quality Assurance’ or ‘QA’ involves making compliance checks at selected, successive stages in the manufacturing process and rejecting any product which fails to meet the criteria of any one check stage. The emphasis of the first method may thus be seen to be on monitoring the quality (‘compliance’) of the finished product and the emphasis of the second method on monitoring the quality (‘compliance’) of the various process steps in the manufacturing method.
It is desirable that the product itself or a support (e.g. a pallet or packaging) associated therewith bears some marking to show that each individual compliance check has been made and complied with. In a multi-stage ‘QA’ type process it may be appreciated to be inconvenient, complex and costly to successively mark the product using traditional printing and bar code methods. Furthermore, the final product will end up with many separate markings thereon which is undesirable from a product aesthetic standpoint.
The Applicants have now devised an improved method of checking compliance in a multi-stage manufacturing method. The method involves associating a memory with an object upon which successive manufacturing operations are to be performed. Following the successful completion of each successive manufacturing operation, a compliance data item is written to the memory. Following the completion of a pre-defined number of manufacturing operations the compliance data items are read from the memory and checked against a compliance data checklist to ensure that the pre-defined number of manufacturing operations has been successfully completed.
The memory can be configured to have a structure which allows for large amounts of discrete information to be stored thereon. Transfer of information to or from the memory is furthermore readily achievable by the use of a reader which is typically but not necessarily remote from the object, thereby miminising the need for direct product handling. In further aspects, the reader can be arranged to simultaneously read the memory of multiple tags on multiple objects.
A principal advantage of the present invention is the capability of the memory to store many items of compliance data which are written thereto at various defined points in the manufacturing method. The memory thereby provides a detailed and readily accessible product compliance history. Such product history information may, for example, be referred to in the event of a product recall. The compliance information could, for example, include data and time stamps. The memory might also be configured to include a unique serial number stored in encrypted form or in a password protectable part of the memory which uniquely identifies the product and therefore may assist in the detection and prevention of counterfeiting. The information could also include basic product information such as the nature of the product and usage information, customer information such as the name of the intended customer and distribution information such as the intended product destination.